A prototype battery-powered plane, called Greased Lightning or GL-10 is pictured flying at NASA's Langley Research Center in this undated handout photo obtained by Reuters May 1, 2015. The plane, which has 10 engines and can take off like a helicopter and fly efficiently like an aircraft, is currently in the design and testing phase. (Photo by Reuters/NASA)

Models at the Sophia Webster presentation during London Fashion Week Spring Summer 2015 on September 14, 2014 in London, England. (Photo by Anthony Harvey/Getty Images)

A model wears a floral head dress as she promotes a chain of garden centres at the Royal Horticultural Soceity's Chelsea Flower Show in London, Britain, May 18, 2015. (Photo by Toby Melville/Reuters)

Elaine Vandiver shares a moment with a two-year old alpaca as they touch noses as she washes him at her farm at 1560 Stateline Road Monday, May 11, 2015, in Walla Walla, Wash. (Photo by Michael Lopez/Walla Walla Union-Bulletin via AP Photo)

Romanian soldiers take part in a joint military exercise with NATO members, called “Agile Spirit 2015” at the Vaziani military base outside Tbilisi, Georgia, July 21, 2015. Georgian soldiers along with U.S. marines and platoon-size units from Bulgaria, Latvia, Lithuania and Romania are taking part in the exercises at the Vaziani military base outside Tbilisi. (Photo by David Mdzinarishvili/Reuters)

A flood-affected couple sits along a flooded roadside under a picture of Jayalalithaa Jayaram, chief minister of the southern Indian state of Tamil Nadu, in Chennai, India, December 6, 2015. (Photo by Anindito Mukherjee/Reuters)

A model showcases designs on the runway at MGPIN 2015 Mao Geping Makeup Trends Launch show during Mercedes-Benz China Fashion Week Spring/Summer 2015 at Beijing Hotel on October 27, 2014 in Beijing, China. (Photo by Feng Li/Getty Images)

In this Wednesday, January 7, 2015 photo, a Sri Lankan Catholic devotee Rita Anthony kisses her rosary as she prays inside her house in Colombo, Sri Lanka. The Vatican has said that it hopes that Sri Lanka's Christians can play a role in helping heal the wounds of the island nation's bloody 25-year civil war, when the Tamil Tiger rebels fought to create a separate homeland in the north for the minority Tamils, who are mostly Hindu. The war came to a bloody end in 2009, but many Tamils say they feel forgotten by the central government, which is dominated by the country's ethnic Sinhala majority, which is overwhelmingly Buddhist. Sri Lanka's Christians come from both the Tamil and the Sinhala communities, making them a natural bridge between the two sides. (Photo by Eranga Jayawardena/AP Photo)